Cagrilintide vs Retatrutide
Two weight-loss research compounds that don't compete for the same receptor at all — one signals through amylin biology, the other through a purpose-built triple hormone-receptor mechanism.
KYIN Peptides stocks Retatrutide. Cagrilintide is not part of our standard catalogue but is available to order.
At a Glance
| Cagrilintide | Retatrutide | |
|---|---|---|
| Category | Weight Loss & Metabolic | Weight Loss & Metabolic |
| Developer | Novo Nordisk | Eli Lilly |
| Receptor target | Amylin receptor (area postrema) | GIP, GLP-1, and glucagon receptors (triple agonist) |
| Regulatory status | Not FDA-approved alone; NDA filed for CagriSema (with semaglutide), decision expected later in 2026 | Phase 3 (TRIUMPH program), not yet approved |
| Strongest published result | ~23% weight loss as CagriSema (REDEFINE-1, combined with semaglutide) | 28.3% weight loss at 80 weeks (TRIUMPH-1, monotherapy) |
| Available from KYIN Peptides | Available to order (not standard catalogue) | Yes, standard catalogue |
How the Mechanisms Differ
Cagrilintide works through an entirely different signaling system from the incretin-receptor drugs it's often mentioned alongside. Amylin is a hormone co-secreted with insulin by pancreatic beta cells, and cagrilintide acts on amylin receptors in the area postrema of the brainstem — a mechanism that doesn't overlap with GLP-1, GIP, or glucagon receptor signaling at all. That's the whole rationale behind combining it with semaglutide as CagriSema: two non-competing appetite-regulation pathways stacked together.
Retatrutide takes the opposite approach — rather than adding a second, unrelated pathway, it's engineered to activate three receptors within the same incretin/glucagon family simultaneously (GIP, GLP-1, and glucagon), extending the single- and dual-receptor agonists that came before it. See its full discovery history, or how it compares to Semaglutide and Tirzepatide.
Clinical Trial Data
Cagrilintide (monotherapy): A Phase 2 dose-finding trial (Lau et al., The Lancet, 2021; 706 adults with overweight or obesity, 26 weeks) found the highest dose (4.5mg) produced a mean weight reduction of 10.8%, versus 3.0% with placebo. Combined with semaglutide as CagriSema, the Phase 3 REDEFINE-1 trial reported roughly 23% weight loss under the treatment-policy estimand — a considerably larger effect, but from a different, combination compound rather than cagrilintide alone. Novo Nordisk has filed an NDA for CagriSema, with an FDA decision expected later in 2026; neither cagrilintide alone nor CagriSema has been approved as of this writing.
Retatrutide (monotherapy): The Phase 3 TRIUMPH-1 trial (2,339 adults with obesity or overweight, without type 2 diabetes) reported a mean weight loss of 28.3% at the 12mg dose over 80 weeks, with 45.3% of participants losing at least 30% of body weight. Retatrutide remains investigational and has not been approved by the FDA or any other regulator.
Why They're Sometimes Compared
Cagrilintide and Retatrutide both sit in current weight-loss research literature, but the comparison is more about strategy than direct competition. Retatrutide represents the "more receptors from the same family" approach that produced tirzepatide before it. Cagrilintide represents the opposite strategy: keep the GLP-1 mechanism as-is, and pair it with an entirely unrelated hormone system (amylin) for an additive effect. Researchers weighing the two are often really asking which strategy for combining mechanisms — more receptors within one family, or stacking unrelated ones — the field will end up favoring.
Cagrilintide vs Retatrutide questions
What is the main difference between Cagrilintide and Retatrutide?
They act on completely different receptor systems. Cagrilintide is an amylin-receptor agonist, working through the area postrema in the brainstem. Retatrutide is a triple agonist activating the GIP, GLP-1, and glucagon receptors. Because the mechanisms don't overlap, they're studied as potentially complementary rather than competing approaches.
Does KYIN Peptides sell Cagrilintide or Retatrutide?
KYIN Peptides stocks Retatrutide as part of our standard catalogue. Cagrilintide is not part of our standard catalogue, but it is available to order — contact us directly and we'll source it for you.
Which has stronger trial data, Cagrilintide or Retatrutide?
As monotherapy, Retatrutide's Phase 3 TRIUMPH-1 trial reported up to 28.3% mean weight loss at 80 weeks, versus Cagrilintide's Phase 2 result of 10.8% at 26 weeks. Cagrilintide's strongest published data is actually as CagriSema (combined with semaglutide), which reported roughly 23% weight loss in its Phase 3 REDEFINE-1 trial — a different compound from cagrilintide alone.
Looking for specs and pricing?
Retatrutide is in our standard catalogue; Cagrilintide can be sourced on request.